The present invention relates to micro spheres. More specifically, the invention relates to sequestering of micro spheres.
Micro spheres are used extensively to capture analytics of interest for various selective assays. For example, micro-sphere-based immuno-assay allows a means of conducting the determination of multiple analytes simultaneously in a single reaction vessel. Molecular reactions take place on the surface of tiny spheres called micro spheres or beads. For each reaction, target molecules are selectively attached to the surface of internally color-coded micro spheres. The assigned color code identifies the reaction throughout the test. The concentration of target molecules is measured using a second kind of molecule called a reporter, which attaches to the target molecule in a sandwich-type reaction.
Early attempts at developing a suitable sequestering cell suffered because of a large pressure drop across the bead barrier. Either the surface area of a porous membrane was too small or where a gap of ca 3 micrometers (μm) was machined, the length of the bead barrier was too short and gave rise to a large back pressure in the sequestering cell. This problem is remedied by the present invention.